Mutagen vs Carcinogen Mutagen and carcinogen are two terms that have a lot in common. There is a potential that a single substance could be both of them at the same time and be only one of the two, as well.
A curb bit is a type of bit used for riding horses that uses lever action. It includes the pelham bit and the Weymouth curb along with the traditional curb bit used mainly by Western riders. Kimblewicks or Kimberwickes are modified curb bits, and a curb bit is used in a double bridle along with a bradoon.
Definition of curb. 1  1 : a bit that exerts severe pressure on a horse's jaws; also : the chain or strap attached to it â see bit illustration. 2  2 : an enclosing frame, border, or edging. 3  3 : check, restraint a price curb government policies that are designed to put a curb on spending.  4 : a raised edge or margin to strengthen or confine.